Oil filler



FIG. 1 is a front elevational view of an oil filer, showing my new design;

FIG. 2 is a right side elevational view;

FIG. 3 is a bottom plan view;

FIG. 4 is a top plan view;

FIG. 5 is a rear elevational view; and,

FIG. 6 is a perspective view. 

The ornamental design for an oil filler, as shown and described. 